The technology studied by the inventors may include the following technology for semiconductors.
Along with the increasing device miniaturization achieved by semiconductor manufacturing technology, the problem of inadequate I/O capability on semiconductor chips is becoming more and more serious.
This problem of inadequate I/O capability is due to an increasing number of circuits as the semiconductor chips become smaller. Moreover as the operation of each circuit speeds up, the I/O processing load needed to implement semiconductor chip functions becomes larger. The number of terminals on a semiconductor chip however is basically determined by the chip size due to restrictions such as wire bonding. The number of terminals does not increase when chips are made smaller so there is no improvement in I/O processing capability.
To resolve the problem of inadequate I/O capability on semiconductor chips, three-dimensional coupling techniques were intensively developed for forming terminals in two-dimensional shapes on the upper surface and lower surface of the semiconductor chip and then stacking the semiconductor chips in multiple layers to transmit information between the stacked chips.
Three-dimensional coupling techniques can be broadly grouped into a contact method that makes the semiconductor chips physically contact each other by way of via holes (or through holes); and a non-contact method that carries out non-contact communication by utilizing coils and capacitors.
The non-contact method includes an inductive coupling method utilizing stacked semiconductor chips formed as coils that cause an electrical current to flow in the coil mounted in the semiconductor chip for transmitting information, to induce a magnetic field, and transmit information by measuring the inductive current occurring in the coil mounted in the semiconductor chip that receives the information. The non-contact method also includes a capacitive coupling method where a capacitor is formed between the semiconductor chip for receiving information and the semiconductor chip for transmitting information, and information is transmitted by charging/discharging the capacitor from the semiconductor chip on the side transmitting the information, and detecting the charge on the capacitor at the semiconductor chip on the side receiving the information.
JP-A No. 2006-066454 discloses an example of technology for transmitting data between chips by utilizing inductive type three-dimension coupling technology. Also, JP-A No. 2004-253186 discloses an example of technology for transmitting data between chips by utilizing capacitive type three-dimensional coupling technology.